Design The investigators will use a single blind case series multiple baseline design with a baseline varying prior to training onset. By randomizing 12 participants over three conditions of different training onset points in time, the investigators will use a variation in baseline which offers the possibility to differentiate between time effects of the Neurofeedback training. All participants will start with a three-session baseline phase which will include a session with questionnaires, interference task training (in order to quickly reach a learning effect ceiling to better be able to observe additional performance change after intervention) and a resting state EEG measurement followed by two other sessions of resting state EEG measurements and the interference task. Participants in group A will then continue with 14 sessions of TBR Neurofeedback training. Group B will receive six extra baseline EEG measurements before they continue with eight TBR Neurofeedback sessions. Group C on the other hand will only receive 14 placebo training sessions after the short baseline phase. Before every TBR Neurofeedbacktraining or placebo training, a four-minute EEG resting-state baseline measurement will be performed.